The present invention pertains to a device for binding sheets by heating.
A device of this type is known for example from EP-B1-0 508 945. This device includes an elongated electrical heating apparatus whose length corresponds to the length of a longitudinal opening in the device, and a provision for switching in order to activate an electrical circuit at the moment when the binding is placed on the heater.
The functioning of this device is such that during the time which it take after the power is switched on before the heater has warmed up, an audible or visible alarm signal is given. The heater itself includes PTC thermistor elements, however, and is consequently self-regulating.
In another device of this type in accordance with DE-C2-38 05 996, there is provision for a computer which can be used together with a probe to sense the width of the covers which are inserted into the opening between the supports and to determine the moment for switching on the timer for the heating element on the basis of this information.
Devices of this sort can be used advantageously for manufacturing book bindings, brochures and the like, or for similar tasks, by gluing the back of a stack of loose sheets against the spine of a binding folder, using a thermoplastic adhesive and applying heat. The sheets can be of paper, cardboard, plastic and/or the like. Naturally such devices are also suitable for enabling the bonding of two or more sheets to each other and/or to the spine of a folder.
The known devices of this type are rather complicated and costly, however, and so it is an object of the present invention to improve on such a device.